Eruptive Process in Children with Osteogenesis Imperfecta

Osteogenesis imperfecta (OI) is a hereditary disorder characterized by bone fragility and skeletal abnormalities. The administration of bisphosphonates (BPs) in children with OI increases bone density. This antiresorptive inhibits osteoclast action, thus altering physiological processes, in which osteoclasts play important roles, such as the eruptive process. The aim of this investigation was to study the eruptive process (dental development of permanent dentition, resorption of temporary dentition, and alveolar eruption of the first permanent molar) in children with OI medicated with BPs and to compare the results with those of a control group. In total, 34 panoramic radiographs of children with OI [mean chronological age of 8.43 (+/- 1.77)] who were medicated with BPs for a period of one year or more were studied and 367 panoramic radiographs of healthy children [mean chronological age of 9.19 (+/- 1.62)] were used as controls. The Demirjian method was used to study the dental development of the seven permanent teeth in the third quadrant. Alveolar eruption of the first permanent molar was considered when perforation of the alveolar bone was produced. The Haavikko method was used to study the root resorption of the five primary teeth in the third quadrant, and software (PixelStick (R)) was used to measure the lengths of the mesial and distal roots of the primary molars. The cumulative dose of BPs was obtained by mathematically calculating the total dosage received (mg)/weight (kg) and multiplying the relative potency of the medication. The Mann-Whitney U test was used for comparisons, and p < 0.05 indicated statistical significance. A delay of 0.95 points in dental development and delayed exfoliation of primary dentition between 1.31 and 1.66 years were described in the study group. A root resorption delay of 11.8% was described among the 5 primary teeth of 23.3% among the single-rooted teeth and of 5.6% among the two-rooted teeth in children with OI medicated with BFs (p < 0.05). Delayed alveolar eruption of the first permanent molar at 0.31 years of age was found in children with OI medicated with BFs. We detected delayed tooth development at one stage of maturation in the study group, which was clinically imperceptible. The dental age (<= 0.55 years) was greater than the chronological age in both groups. We also reported delayed exfoliation of the primary dentition (from 1.31 to 1.66 years), delayed root resorption of the primary dentition (11.8%), and delayed (from 1 mm to 1.25 mm) root resorption of the primary molars in the study group. Although the degree of dental development of the first permanent molar was similar between the two groups, we found delayed (0.31 years) alveolar eruption in the study group and a greater delay (0.44 years) in children whose cumulative dose of bisphosphonates exceeded 2000.